This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a multi-center protocol examining the effects of Clomiphene as opposed to Letrozole in the promotion of fertility in women with polycystic ovarian syndrome. A total of 750 patients will be randomized across a number of centers. The primary study endpoint is live birth after randomization to one or the other therapy.